This code cannot be parsed due to Invalid expression / Unexpected token. Line 1, Col: 17

from sqlglot import parse_one

s = "insert into t1 t1 (col1) SELECT 1935 AS col1 from duel"

parse_one(s, dialect="oracle")

The statement will parse correctly if AS is added for table alias, i.e. t1 AS t1

However, as per Oracle INSERT syntax documentation, AS is not required for table alias in the INTO